Fluid-pressure-control apparatus



Sept. 18,1923.

' 5. H. LEWIS FLUID PRESSURE CONTROL APPARATUS Filed Nov. 19, 1920 6Sheets-Sheet 1 (Jl'l'orucl Sept. 1a, 1923.

1,468,48fi s. H. LEWIS FLUID PRESSURE CONTROL APPARATUS Filed Nov. 191920 6 Sheets-Sheet 2 5. H. LEWIS I FLUID PRESSURE CONTROL APPARATUSFiled Nov. 19. 1920 s Sheets-Sheet 5 Sept. 18, I923. EAGEASR s. H. LEWISFLUID PRESSURE CONTROL APPARATUS Filed Nov. 19, 1920 s Sheets-Sheet 4gag;

Sept. 18 1923. 1,468,481

S. H. LEWIS FLUID PRESSURE CONTROL APPARATUS Filed Nov. 19. 1920 6Sheets-Sheet 5 64 6/ ii' @5 29 'v '70 Sept. 18,1923. 1,468,481

. s. H. LEWIS FLUID PRESSURE CONTROL APPARATUS I Filed Nov. 19, 1920 sSheets-Sheet 6 q m a I b g b b I m r &w%

Patented Sept. l8, 1923.

nears rarest or;

SAMUEL LEWIS, OF RICHMOND, VIRGINIA.

FLUID-PRESSURE-CONTROL APPARATUS.

To aZZw/"mmitmay concern:

e it known that I, SAMUEL H. LEWIS, a citizen of the United States,residing at Richmond, in the county of Henrico and 5 State of Virginia,have invented certain new and useful Improvements in Fluid-Pressure-Control apparatus, of which the following is a specification.

This invention relates to fluid pressure 1 controlled apparatus forsupplying steam to the cylinder or cylinders of railway locomotives whenthe main supply of steam is cut off and the engine is drifting bygravity or under its own momentum.

.Railway locomotives are frequently operated by superheated steam whichis heated to a temperature of about 600 F. T hishigh temperature heatsthe walls of the cylinder of the engine so that oil used for-lubricationwill be burned or flashed upon introduction of air into the cylinders ofthe locomotive. W hen the main supply of steam is cut off, air will bedrawn into the cylinders by the movement of the pistons, a partialvacuum being created therein. The present invention r lates to means forintroducing suliicient steam into the cylinders when the main valve iscut off and the engine is drifting, to

prevent formation of a'vacuiim within the,

cylinder and the resulting admission of air.

In a prior application, Serial No. 245,936,

I employ a pressure chamber having a pair of valves arranged therein,and a valve actuating member connected to a moving part of the enginefor-the purpose of alternately opening and closingsaid valves, wherebyair under pressure is delivered to a chamber having a piston thereinconnected to the drifting steam valve.

49 sure has been built up in said chamber, the

drifting steam valve is opened and will re main open as long as thespeed of the engine is sutlicient to operate the valves in the pressurechamber at such speed that compressed air or other gas will be deliveredto the chamber associated with the drifting steam valve at a ratesuflicient 'to maintain the proper pressure therein.

In the present invention, 1 have produced an apparatus embodyingthefeatures of my prior lDVcnldOI]; wherein the chamber associated withthe drifting steam valve communicates with the drifting steam pipe, orthe main stea a pipe, to establish pressure on the opposlte side ofSflCljDlStQll equal to the Vfhen suitable ores pressure in the steamchest. By means ,of the present invention sutlicient steam is fed to thecylinders to preventthe formation ofa vacuum therein when the engine isdrifting above a predetermined speed and at the same time, means areprovided for automatially shutting off the drifting steam supply when apredetermined pressure is present in the steam chest indicating thepresence of sutlicient steam to prevent the formation of vacuums withoutthe necessity of introducing additional steam through the drifting steamvalve. Y

As in my prior application, when the speed of the engine decreasesbeyond a predetermined point, as when the engine is about to stop, thedrifting steam valve will be closed by the decrease of pressure in thechamber associated with the drifting steam valve regardless of-thepressure in the steam chest.

By varying the areas on the opposite side of the piston in the chamberassociated with the drifting steam valve, the pressurenecesnary in thesteam chest to overcome the pressure of the compressed air on the pistonmaybe adjustedand thus the pressure at which the drifting steam valvewill be closed, due to the presence of sufiicient steam inthe steamchest, may be varied. i 35 In the accompanying drawings, I have shownoneembodiment of the invention. In this showing: i

Figure 1 is a side elevation of a railway locomotive showing theinvention applied thereto,

Figure 2 is a side elevation of the pressure chamber and associatedparts,

Figure 3 isa vertical transverse sectional view thereof,

Figure l is a transverse vhorizontalsectional view on line44 of Figure2,

Figure 5 is a side elevation of the mechanism for actuating the valvesin the pressure chamber. parts of the pressure chamber being shown insection Figure 6 is a sectional .view on line 6-6 of Figure 2,

Figure 7 is a detail perspective view of one of the valves employed inthe pressure chamber,

Figure 8 is a similar view of the other valve, 7 V

Figure 9 is a detail perspective view of a y portion of the valveactuating mechanism,

point on the locomotive.

Figure 10 is a sectional view of one form of drifting steam valve andassociated elements,

Figure 11 is a similar view showing a slightly different arrangementofparts, and,

Figure 12 is a sectional view showing another type of drifting steamvalve.

Referring to the drawings, the reference numeral 1 designates a railwaylocomotive of any suitable type having a sand box 2 and a steam dome 73,as shown. The locomotive is provided with the usual cylinder 3 and steamchests a are arranged above the cylinders in the usual manner. A steamsupply pipe 5 is connected to the steam chest. The usual distributionvalve (not shown) is arranged within the steam chest and operated by aradius rod 6 in the usual manner.

Referring more particularly to Figures 2 to 9 of the drawings, thenumeral 7 designates a control apparatus or pressure chamher which maybe supported at any suitable As shown, is formed with lugs 8 havingopenings 9 whereby it may be arranged on the valve chest head bracket 10of the locomotive. A

pair of chambers 11 and 12 are arranged within the pressure chamber, oneo! said chambers being provided with a pipe busln ing 13, having anopening 14: arranged therein. The upper end of the other chamber isclosed by a threaded plug l5. A pipe 16 is connected to the opening l-fland communicates with a tank 17, containing compressed air or other gasat suitable pressure above atmospheric pressure. If desired, a gasfilter 18, packed with suitable filtering material 19 may be arranged inthe pipe .16 (see Figure 2). The lower end of the chamber ll is providedwith a valve seat 20 and a valve 21 is arranged in the chamber. Asshown, the valve is provided with a taco adapted to engage the valveseat when in closed position. A spring 24 is arranged between the top ofthe casing and the valve to normally hold it in closed position. Thevalve stem 25 extends through an opening 26 in the bottom of thechamber, which, as shown, is oi? g tater diameter than the diameter oi?the stem to 1 iermit passage oi? air or other fluid. This openingeommuni ates with the main pressure chamber 27, which is preferably madeconsiderably larger-than the chamber 11. The lower end of the chamber 12is provided with an opening 28 and an outlet chamber 29 is arrangedbottom of the pressure chamber having an opening in'alinement with theopening 28. This opening is provided with a valve seat 30, adapted to been wed by a valve 81 havingza valve I which extends through the opening28. A spring 83 is arranged on top of the stem to normally retain thevalve in closed position. Beneath the. valve at the her through anopening in the bottom of the chamber 27 when the valve is open. Theoutlet chamber is provided with an outlet opening 37 and with a drainopening in alinement with openings 28 and 35, which is normally closedby a threaded plug 38.

The valves 21 and'31 are adapted to be alternately opened and closed topermit passage of air under pressure l rom the inlet 14 to the outlet37. Means are provided whereby the valves are alternately opened andclosed at a speed proportionate to the speed of travel of the engine.The lower end of the pressure chamber is provided with a sub stantiallycircular extension 39 arranged at right angles to the body portion andadapted to receive a substantially cylindrical membereltl. hesubstantially cylindrical member 4-0 is secured to the extension bymeans of screw-threads all. As shown, this member is adapted to form abearing for horizontal rock shaft 42, the inner'end of which is providedwith a substantially T-shaped operating member one end -14 of which isadapted to engage the valve stem 25 when the shaft is rocked in acounterclockwise direction and open valve 21. The other end of theT-shaped member operates in a recess 4-6 in the valve stem 32 (seeFigure 9) and is adapted to" engage a shoulder it? formed by the recesswhen the valve is operated in a clockwise direction to raise the stemand open valve 31.

Referring to Figure l olthe drawings, the end of the rock shaftis'enlarged, as at 48,

andthe cylindrical member 40 is provided with a redured opening 49,whereby the in nor end of the cylindrical member 40 will engage the end48 and retain therock shaft in position. The oppositeend of thecylindrical'memher 410 is threaded. as at 51, for the reception of ahollow nut 52, having a reduced opening in its outer end, providing ashoulder 53. it lever. 54- is secured on the outer end of the rockshaft, and this lever.

arranged around rock shaft 42. the packing being held in position by apacking gland 59. The packing glandis provided with a rib 60. adapted tobe engaged by the nut 52 to permit tightening of the packing 59.

Re"rring to Figure 1, 2,'and 10 of the drawngs. a pipe 60 is connectedto the outlet opening 3? of the pressure chamber, and this pipecommunicates with a cylinder 61, a-r-' ranged adjacent the valve casing62. A pisten 63 is arranged in the cylinder, the piston loosely fittingthe cylinder to permit leak-' age of air into the lower portion of thecylinder, whereby the air is exhausted to the atmosphere through opening6d. As shown, the upper portion of the cylinder is of smaller diameterthan the lower portion, an auxiliary cylindrical member 65 beingarranged in the upper ortion, the member beingcarried by the. cylinderhead 86 which is secured to the cylinder proper by meansot bolts 67. Thepiston likewise comprises an upper portion 68 and a lower portion 69.

Thelower portion of the piston is provided with rings 70 to preventleakage of steam from the lowerside of the piston to the atmospherethrough opening 64-.

' The valve casing 62 isprovided with an inlet 7l 'andian outlet 72. Theinlet isin communication with a steam dome 73 through the medium of pipe74,'and the outlet is incoinmunication with the main steam pipe throughthe medium .of pipe 7 A drifting steam valve 76 is arranged in the valvecasing and is normally maintained on valve seat 77 by a coil spring 7 8arranged in V the lower portion of thecylinder 61 and en-' gaging aplate Or washer 7 9,-carried by the upper end of the valvestem 80. Asshown, the valve stem extends through an opening in the bottom of thecylinder 61 and is pro? vided with a threaded end 81 for thereception ofa nut 82, whereby the washer 79 is retained on the stem. The nut beprovided with suitable locking means such as pin 88, adapted toextend-through alining openings in the nut and the end of the valvestem. The valve casing is provided with a port 'Sji-to permitintroduction of steam into" mosphere, the diameter of the piston beingslightly smaller than the diameter ot the cylinder, whereby flow of airtolthe exhaust opening 64 at a retarded speed, is permitted. 1 ln'theconstruction shown in Figure 12 of the drawings, thedrit'ting valveinletand outletjopenings are arranged in alinemcnt with eachotherinstead ofat right angles. The construction of the piston and cylinder issubstantially the same as in Fgure 11 of the drawings, but the parts arevshown arranged reversely with the valve76 opening upwardly instead ofdownwardly.

vacuum in the cylinders. 'The control ap paratus is operated at a speeddirectly proportionate to the speed of the locomotive, whereby thesupply of drifting steam will be cut as when the speed of the enginedrops below a predetermined speed, as when thelocomotive is about tostop and presence of steam in the cylinder is undesirable. When theengine isrunning, the rock shaft 42 is oscillated at aspeed directlyproportionate to the speed of the locomotive through lever 54. Thevalves 21 and'3l are alternately opened and closed, whereby air underpressure passes from the tank 17 through pipe 16, chamber 11 to the bodyof the pressure chamber and thence to the outlet chamber 29. From theoutlet chamber 29, it is conveyed to the cylinder 61, through pipe (30,and when the speed of the engine is sutlicieut to supply compressed airto the chamber (St) ata rate greater than the rate of exhaust throughthe opening 64:, a pressure built up in the cylinder 60, which when themain throttle valve is closed, moves the piston 63 downwardly intoengagement with the valve stem 80, and forces the valve stem downwardlyagainst the tension of spring 78 and steam pressure below valve 76, toopen valve 76. When valve 76 is opened, steam is sup plied to the steamchests ot' the engine thron -h iies 7d and Y5, and main steam pipe 5."As soon as the speed of the engine dropsto a point where the valves 2ian 31 are not operated with sutlicient rapidity to supply air to thecylinder 61, at a greater rate than the rate of exhaust throughopeningbi, the piston 63 will be mov-d upwardlyby spring 78 and stean admittedthrough port 8% outof engagement with valve stem 80 and the valve 76will be closed by the spring 78.

in addition to the means whereby the drifting valve is automaticallyclosed when the engine is drifting below a predetermined speed, meansare provided for automatically closing the drifting steam valve when thepressure in the steam chest is sufiicient to inpressure is communicatedto the lower side of the piston and counteracts the pressure of thecompressed air supplied by the control apparatus. In the form of theinvention shown in Figure l0 of the drawings the leakage past thesmaller end of the piston is substantially equal to the leakage throughport whereby no pressure will be built up above the larger end of thepiston between the auxiliary cylindrical member 65 and the cylinderwall. 'l here'iore, the lower efl'ective area of the piston issubstantially twice great as the upper effective area, whereby thepiston will be moved upwardly by a lower pressure exhausting in thesteam chest. ll hen the pressure in the lower end of the cylinder issuliicient to more the piston upwardly out of contact with the valvestem, the valve is closed by spring 78 and the supply'ot drifting steamis cut off.

in the form of the invention shown in Figures 11 and 12 of the drawings,the operation is the same, except that the piston is of substantiallythe same diameter throughout and its upper and lower areas aresubstantially equal. in either of these two formsof the inventionagreater pressure is necessary in one end of the cylinder to offset theair pressure in the opposite end and move the piston. to the end of thecylinder to permit the valve to close. By regulating the effective areasof the upper and lower taces of the piston, the pressure in one end ofthe cylinder necessary to offset the pressure'in the opposite end may beadjusted within wide limits.

While I have shown and described the preferred embodiments of myinvention, it is to be understood that various changes in the shape,size, and arrangement ot'parts, may be resorted to without departingfrom the spirit of the invention or the scope of the subjoined claims.

Having thus described my invention, 1 claim:

1. In apparatus for supplying steam to the cylinders of steamlocomotives while in motion. a fluid pressure control member connectedto a movable part of a locomotive to move in unison therewith anddeliver fluid pressure therethrourrh in proportion to the speed of thelocomotive, a cylinder communicating; with said control member, saidcylinder being arranged adjacent the steam supply pipe, a valvemounted-in said supply pipe, piston mounted in said cylinder andconnected to said valve. said cylinder being provided with means topermit the gradual exhaust of a portion of the fluid delivered thereto,whereby the piston therein-will be actuated to open the valve when thespeed of the locomotive exceeds a predetermined point, and means forsupplying steam to said cylinder on the opposite side of the piston to"counteract said fluid under pressure.

2. In apparatus for supplying steam to the cylinders of steamlocomotives while in motion, a fluid pressure control member connectedto a movable part of the locomotive to operate inunison therewith, acylinder communicating with said control member, a steam supply pipearranged adjacent said cylinder, a piston mounted'in said cylinder, avalve mounted in said pipe and connected to said piston, said cylinderbeing provided with a leak port to permit gradual exhaust of fluidtherefrom, whereby the control member will supply sufiicient fluid tothecylinder to maintain a pressure therein when the locomotive assumes apredetermined speed, and means for supplying steam to the opposite endof the cylinder to counter-act said tluid under pressure.

3. in apparatus-for supplying steam to the cylinders of steamlocomotives while in motion, fiuid pressure motor having a slow leaktherein whereby said motor is only actuated when a predetermined amountof fluid under pressure is admitted. thereto, means to supply steam tothe cylinders opcrated by said fluid pressure motor, means for supplyingfluid under pressure to said motor, and means for supplying steam tosaid motor to counter-act the effect of said fluid under pressure. 7

4; lin )aratus for'supplying steam to the cylinders of a railwaylocomotive while moving. fluid pressure motor having a slow leaktherein, means to supply steam to the cylinders operated by said fluidpressure motor, a pressure chamber to supply fluid under pressure to themotor, means to control the inlet and outlet of fluid pressure to andfrom the chamber, said control means being connected with a-movable partof the locomotive to operate in unison therewith, and means forsupplying steam to said motor to counter-act the effect of said fluid,said motor, being adapted to operatewhen the speed of the locomotiveexceeds a predetermined point.

5. The combination with the steam engine of a locomotive, said enginecomprising a steam chest, of means for supplyingsteamto said steam chestwhenthelocomotive isinmotion and the throttle is closed, said meanscomprising a fluid pressure motor having a slow leak therein, means tosupply steam to the steam chest operated by said fluid pressure motor, apressure chamber to supply tluid under pressure to the motor, means tocontrol the inlet and outlet of fluid to and from the pressure chamber,said control means being connected to a movable part of the locomotivetomove in unison therewith, and means for supplying'steam to the motorfrom the steam chest to counterilCiTtllG effect of said fluid wherebythe motor is normally set in action when the speed of the locomotiveexceeds a predetermined iai point, but is rendered inoperative when thepressure in the steam chest exceeds a predetermined point.

6. The combination with the steam engine of a locomotive, said enginehaving a steam chest, of means for supplying steam to the steam chestwhen the locomotive is in mowhen .the pressure therein reaches a prede-.termined point, a pressure chamber to supply fluid to the motor, meansto control the inlet and outlet of fluid to and from the chamben saidcontrol means being connected to a movable part of the locomotive tooperate in unison therewith, and means for supplying steam fromthesteamchest to said motor to counter-act the eflect of said fluidwhereby the motor is normally set in action when the speed of thelocomotive exceeds a predetermined point, but is renderedinoperative'when' the pressure in the steam chest I exceeds apredetermined point.

7. The combination with the steam chest of a locomotive engine, of meansfor supplying steam to said steam chest when the locomotive is in motionand the throttle is closed, said means comprising a fluid pressuremotor, said fluid pressure motor being provided with means to permitgradual exhaust of fluid therefrom, said motor being set in operationwhen the flow ot'fluid therethrough reaches 'a predetermined point,means to intermittently supply fluid to the motor, said supplymeans-being connected with a movable part of the locomotive, and

.means' for supplying steam from the steam chest to said motor tocounter-act the effect of said fluid whereby the motor is normally setin action when the speed of the locomo means comprising a fluid pressuremotor, said motor having means to permit the gradual exhaust of aportion of the fluid supplied thereto, means operated by said motor tosupply steam to the steam chest, said motor being set in operation Whenthe pressure therein reaches a predetermined point, a pressure chamberto supply fluid to the motor, operating'means for said pressure chamberconnected to a movable part of the locomotive to be operated thereby tocontrol the inlet and outlet of fluid to and from the chamber, saidmotor being provided with an opening communicating with the steam supplywhereby steam from the steam chest will be delivered to said motor tocounter-act the effect ofthe fluid therein and render said motorinoperative when the pressure in the steam chest exceeds a predeerminedlimit.

9. The combination with the steam engine of a locomotive, said enginehaving a steam chest, of means for supplying steam to said steam chestwhen the locomotive is in motion and the throttle is closed, said meanscomprising a fluid pressure motor, said motor having means to permit thegradual exhaust of a portion of the fluid supplied thereto, means tosupply steam to the steam chest operated thereby, said fluid pressuremotor being set in action when the fluid pressure therein reaches apredetermined point, a pressure chamber to supply fluid to the motor,means connected with a movable part of the locomotive to control theinlet and outlet of fluid to and from the chamber, said motor beingprovided with an opening arranged opposite the fluid pressure inlet andcommunicating with the steam supply means whereby steam from the steamchest will be delivered to the motor to counter-act the eliect of thefluid therein and render the motor inoperative when the steam pressureSAMUEL HANCE LEWIS.

Vitnesses:

Rona. H. TALLER, THOMAS B. Smon.

